Shari this was my first salvia. It will grow huge, at least 4'X4'. If your half barrel is really big it might work but be prepared for the stalkes to fall over. If you have a nice big empty spot in your garden it will do real good there.

mimidi is right.

I planted mine about 2 months ago. It was no more than a foot tall. Guess what, it is over 3 feet tall already.

I planted mine out in a bed with only morning sun. It gets to about 3' x 3' for me, but I know some get bigger. The thing that I like about it is that it is a non-invasive salvia unlike a lot of them. And the hummers really like mine. Mine died back this year with the snow, but have come back looking really great.

My plants are growing rather slowly, less than a foot in a month. Is this one of those plants that doesn't really start to role until the weather warms up; we haven't had any hot weather yet. Lastly, the plant is rated hardy to zone 7. Has anyone carried over in zone 7 or zone 6?

Second year for mine. Tall and lanky. I have 2 tomato cages around it, one inverted. It broke easily last year. It didn't seem too like it when it got real hot here but it may be because it doesn't get sun until around noon. Mine came back after lows of 24* this winter - it was mulched.

It's not hardy for me but it sure is big at least 2or 3 feet and it was only a foot or less two weeks ago. Sarah

Phoebe, same thing here. I noticed now that it is getting tall & lanky. There are about 4 plants going up and out from the center. Is this normal for this plant? I always like to try new salvias but I cant stand the lankiness in plants. Drives me nuts to have to stake and tie like crazy.

I have never had to stake mine, nor do I know anyone down here that has had that problem. Maybe they are not getting enough sunlight.

Indigo Spires states:

Culture
Indigo Spires tends to keep growing and growing and then falling over under its own weight. Constant pruning and pinching will keep it in bounds, and removing the flower spikes after most of the flowers have dropped off will encourage more blooming.

Light: This salvia does best in full sun, but does okay in part shade, too.

Moisture: Indigo Spires needs regular watering to be at its best, but can tolerate drought if it has to.

Hardiness: USDA Zones 7 - 11. Indigo Spires dies to the ground after frost and returns reliably in spring.

Propagation: Indigo Spires is a sterile hybrid, so don't bother with seeds. Fortunately, it is very easy to root from cuttings.

'Indigo Spires' is becoming popular in the UK. It is a great Salvia...I would agree that is does need some staking, as the large flower-heads can cause it to flop. I followed Betsy Clebsch's recommendation of partnering this Salvia with Gaura lindheimeri, and this is a great partnership. The deep blue and white complement each other so well. Add a few S. uliginosa and the orange S. darcyi, and you will have the most spectacular combination of colours.

Robin.